Based on kernel version 3.0.4. Page generated on 2011-10-03 22:07 EST.
1 <refentry id="vidioc-overlay"> 2 <refmeta> 3 <refentrytitle>ioctl VIDIOC_OVERLAY</refentrytitle> 4 &manvol; 5 </refmeta> 6 7 <refnamediv> 8 <refname>VIDIOC_OVERLAY</refname> 9 <refpurpose>Start or stop video overlay</refpurpose> 10 </refnamediv> 11 12 <refsynopsisdiv> 13 <funcsynopsis> 14 <funcprototype> 15 <funcdef>int <function>ioctl</function></funcdef> 16 <paramdef>int <parameter>fd</parameter></paramdef> 17 <paramdef>int <parameter>request</parameter></paramdef> 18 <paramdef>const int *<parameter>argp</parameter></paramdef> 19 </funcprototype> 20 </funcsynopsis> 21 </refsynopsisdiv> 22 23 <refsect1> 24 <title>Arguments</title> 25 26 <variablelist> 27 <varlistentry> 28 <term><parameter>fd</parameter></term> 29 <listitem> 30 <para>&fd;</para> 31 </listitem> 32 </varlistentry> 33 <varlistentry> 34 <term><parameter>request</parameter></term> 35 <listitem> 36 <para>VIDIOC_OVERLAY</para> 37 </listitem> 38 </varlistentry> 39 <varlistentry> 40 <term><parameter>argp</parameter></term> 41 <listitem> 42 <para></para> 43 </listitem> 44 </varlistentry> 45 </variablelist> 46 </refsect1> 47 48 <refsect1> 49 <title>Description</title> 50 51 <para>This ioctl is part of the <link linkend="overlay">video 52 overlay</link> I/O method. Applications call 53 <constant>VIDIOC_OVERLAY</constant> to start or stop the 54 overlay. It takes a pointer to an integer which must be set to 55 zero by the application to stop overlay, to one to start.</para> 56 57 <para>Drivers do not support &VIDIOC-STREAMON; or 58 &VIDIOC-STREAMOFF; with <constant>V4L2_BUF_TYPE_VIDEO_OVERLAY</constant>.</para> 59 </refsect1> 60 61 <refsect1> 62 &return-value; 63 64 <variablelist> 65 <varlistentry> 66 <term><errorcode>EINVAL</errorcode></term> 67 <listitem> 68 <para>Video overlay is not supported, or the 69 parameters have not been set up. See <xref 70 linkend="overlay" /> for the necessary steps.</para> 71 </listitem> 72 </varlistentry> 73 </variablelist> 74 </refsect1> 75 </refentry> 76 77 <!-- 78 Local Variables: 79 mode: sgml 80 sgml-parent-document: "v4l2.sgml" 81 indent-tabs-mode: nil 82 End: 83 -->
